I'm looking for a lens to replace my Canon, I'm finding my lens abit too slow in terms of lighting conditions.
I have read through the reviews of both Sigma & Tamron lens, but I'm still stuck in choosing which lens will be a better buy.
1 issue is that both Sigma & Tamron have no IS, so does a lower F-stop help to balance out the IS factor?
Another thing I'm wondering over is the focal length. Is there a big difference between 17-50 & 18-55?
Which lens is sharper at the longest focal length for Tamron & Sigma?